Cisco router 4331 with home router

[ayysangpham]

Hello Cisco Community,

I have a Cisco Router 4331 with an 8-port switch module. My currently ISP is starlink and receiving IP by DHCP. I want to connect my home router that is currently providing all my wifi. I want to run it through this router instead of connecting it directly because of the current infrastructure in place. This router currently provides internet through another network. I want both my other network and home network to go out to the internet on the same interface.

1. should i connect the home router into one of the switch-ports and trunk it? what settings would I need for traffic to flow from the switch port to my ISP gig interface?

2. should i connect it to one of the routers gi interfaces.

3. i dont have much experience with configuring these routers, but i assume if i go with option 2 that it would include setting an ip for my inside interface, NAT, and ip routes.

Any assistance with where i should start will be greatly appreciated. Thank you

Andre

[Kasun Bandara]

@ayysangpham hi, without understanding about current configuration, its difficult to guide with those options. can you share current configuration of main router and small map how devices are connected.

[MHM Cisco World]

totally correct 
we need simple topology here 

BUT 
do I need NAT ? Yes you need NATing 
how can I make this home router is GW to internet ? If the SW is L3 you need only default route toward this home router, if the SW is L2 then you need to push this home router IP as default-router IP via DHCP to all host. 

[M02@rt37]

Hello @ayysangpham,

--Connect your home router to one of the gigabit interfaces on the Cisco Router 4331,

--Configure the gigabit interface on the Cisco Router 4331 with an IP address in a separate subnet from your other network,

--Configure NAT on the Cisco Router 4331 to translate the source IP addresses of your home network to the IP address of the gigabit interface,

--Set up IP routes on the Cisco Router 4331 to ensure that traffic from your home network is routed to the ISP gigabit interface,

--Configure your home router with an IP address in the same subnet as the gigabit interface on the Cisco Router 4331,

--Set the default gateway on the home router to the IP address of the gigabit interface.

[ayysangpham]

i configured on home network on my switch module and created a vlan 100. I gave that interface access to vlan 100 and set the default gateway ip for vlan 100. My ISP is on Gi0/0/1 and my second network is on gi0/0/2. my ISP ip is DHCP and my home network is 192.168.14.1 and my private lan under the home network is 192.168.0.1. right now i can ping my home router from the Cisco router. I think what i am missing is an ip route that routes my home/private lan to my ISP. i am not too great at IP routes, if i could get some examples of commands to input. my router currently has a bunch of different extended access list as well.

[ayysangpham]

This is my basic topology.

[MHM Cisco World]

[M02@rt37]

Hello @ayysangpham,

As I suggest to you:

--Connect your home router to one of the gigabit interfaces on the Cisco Router 4331,

--Configure the gigabit interface on the Cisco Router 4331 with an IP address in a separate subnet from your other network,

--Configure NAT on the Cisco Router 4331 to translate the source IP addresses of your home network to the IP address of the gigabit interface,

--Set up IP routes on the Cisco Router 4331 to ensure that traffic from your home network is routed to the ISP gigabit interface,

--Configure your home router with an IP address in the same subnet as the gigabit interface on the Cisco Router 4331,

--Set the default gateway on the home router to the IP address of the gigabit interfa

--Set up static IP routes on the Cisco Router 4331 to ensure that traffic from outside go back to your home network

--Set up default ip route on the Cisco Router 4331 to dhcp to ensure that traffic from home network go to ouside

--Set up default ip route to ISR Gi 0/0/3 to ensure that traffic from your LAN go to your ISR home router